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Isolation and Identification of Waterborne Antibiotic-Resistant Bacteria and Molecular Characterization of their Antibiotic Resistance Genes
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Published on: March 3, 2023

Clonal spread of emm type 28 isolates of Streptococcus pyogenes that are multiresistant to antibiotics

Liliana Mihaila-Amrouche1, Anne Bouvet, Julien Loubinoux

  • 1Centre National de Référence des Streptocoques, Service de Microbiologie, Hôtel Dieu, Assistance Publique-Hôpitaux de Paris, Université Paris V, 1 place du Parvis Notre-Dame, 75181 Paris Cedex 04, France.

Journal of Clinical Microbiology
|August 7, 2004
PubMed

Insights

Multiresistant Streptococcus pyogenes strains, resistant to bacitracin and other antibiotics, were identified. These invasive isolates were found to be of emm type 28 and clonally related.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Antimicrobial Resistance

Background:

  • Streptococcus pyogenes (Group A Strep) is a significant human pathogen causing pharyngitis and invasive infections.
  • Emergence of antibiotic resistance in S. pyogenes poses a threat to effective treatment.
  • Bacitracin resistance in S. pyogenes is uncommon, making resistant strains of clinical interest.

Purpose of the Study:

  • To characterize the antibiotic resistance profiles of bacitracin-resistant Streptococcus pyogenes isolates.
  • To determine the emm types and genetic relatedness of these multiresistant strains.

Main Methods:

  • Collection and phenotypic antibiotic susceptibility testing of 53 S. pyogenes isolates resistant to bacitracin.
  • Molecular characterization including emm typing and pulsed-field gel electrophoresis (PFGE) for genetic relatedness assessment.

Main Results:

  • All 53 collected S. pyogenes isolates exhibited resistance to bacitracin.
  • These isolates were also resistant to streptomycin, kanamycin, macrolides, lincosamides, and streptogramin B, indicating multidrug resistance.
  • All multiresistant isolates belonged to emm type 28.
  • Pulsed-field gel electrophoresis demonstrated that these emm type 28 isolates were clonally related.

Conclusions:

  • The study identified a clonal group of multidrug-resistant Streptococcus pyogenes (emm type 28) exhibiting resistance to bacitracin and other key antibiotic classes.
  • This finding highlights the potential for the emergence and spread of highly resistant S. pyogenes strains.
  • Further surveillance is warranted to monitor the prevalence and clinical impact of such multiresistant isolates.

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